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排序方式: 共有376条查询结果,搜索用时 15 毫秒
51.
P A Stewart 《Experimental neurology》1980,67(2):442-446
It has been proposed that γ-glutamyl transpeptidase (GGTP) is involved in amino acid transport across the blood-brain barrier. A controversy exists, however, about whether or not sufficient GGTP activity is present in chick brain capillaries to be demonstrated histochemically. Under conditions in which GGTP was readily demonstrated in chick kidney, hamster kidney, and hamster brain capillaries, no GGTP activity was present in chick brain capillaries. Therefore, it is unlikely that GGTP activity is present in sufficient quantity in chick brain capillaries to account for all amino acid transport across the blood-brain barrier. 相似文献
52.
Liang Zhao Shuangjiang Li Juan Ju Haining Zhou Hongyu Wang Guowei Che 《Annals of thoracic and cardiovascular surgery》2021,27(3):151
Background: We report this propensity score matching (PSM) analysis to assess prognostic roles of preoperative gamma-glutamyl transpeptidase to platelet ratio (GPR) in video-assisted thoracoscopic (VATS) lobectomy for stage I-II non-small-cell lung cancer (NSCLC).Methods: The PSM-based study conducted on our single-center prospectively collected database from January 2014 to August 2015 provided Kaplan–Meier survival analyses using the log-rank test to discriminate differences in overall survival (OS) and disease-free survival (DFS) between patients stratified by preoperative GPR.Results: Our study includes 379 patients diagnosed with operable primary stage I-II NSCLC. A GPR value at 0.16 was recognized as the optimal cutoff point for prognostic prediction. Both OS and DFS of patients with GPR ≥0.16 were significantly shortened when compared to those of patients with GPR <0.16. Patients with GPR ≥0.16 had significantly lower 5-year rates of OS and DFS than those of patients with GPR <0.16 (P <0.001). Significant associations between GPR and unfavorable survival still are validated in the PSM analysis. Multivariable Cox regression models on both the entire cohort and the PSM cohort consistently demonstrated that an elevated preoperative GPR could be an independent prognostic marker for both OS and DFS of resectable NSCLC.Conclusions: GPR may be an effective and noninvasive prognostic biomarker in VATS lobectomy for surgically resectable NSCLC. 相似文献
53.
Ganesan Pushpavalli Chinnadurai VeeramaniKodukkur Viswanathan Pugalendi 《Food and chemical toxicology》2010
Chrysin is a flavonoid that exists in nature and is the major component of some traditional medicinal herbs. We investigated the hepatoprotective and antihyperlipidaemic potential of chrysin against d-galactosamine (a single intraperitoneal injection 400 mg/kg BW) induced hepatotoxicity in male albino Wistar rats. d-GalN rats exhibited an increased hepato and nephro toxicity marker activities aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and gamma glutamyl transpeptidase and total bilirubin level while urea, uric acid and creatinine and lipid profile. It also negatively affected the serum total protein, albumin and A/G ratio. Rats treated with chrysin at different concentrations (25, 50 and 100 mg/kg BW) caused a significant improvement in serum protein level, decreased hepato and nephro toxicity markers. It also decreased the levels of very low density lipoprotein cholesterol and low density lipoprotein cholesterol while high density lipoprotein cholesterol significantly increased. It also decreased the levels of total cholesterol, phospholipids, triglycerides, free fatty acids in the plasma and tissues of liver and kidney. The effect of chrysin (25 mg/kg) is comparable with silymarin, a known hepatoprotective drug. Chrysin thus exhibits hepatoprotective and antihyperlipidaemic activity. 相似文献
54.
目的 探讨邯郸矿业集团225名矿处级体检干部中,脂肪肝组与非脂肪肝组血液部分生化检测指标间的关系,提醒其关注自身健康.方法 对邯郸矿业集团总医院2010年7~11月体检中心接诊的225名矿处级干部的三酰甘油(TG)、空腹血糖(FPG)、γ-谷氨酰转移酶(γ-GGT)、血尿酸(UA)检测指标进行回顾性调查分析,并按其是否患有脂肪肝将结果分为两组,并进行统计学分析研究.结果 脂肪肝组与非脂肪肝组的TG、FPG、γ-GGT、UA异常检出率分别是59.84%、41.73%、74.02%、15.75%和24.49%、18.37%、18.37%、1.02%,脂肪肝组各项指标异常检出率均明显高于非脂肪肝组,两者差异有统计学意义(P<0.01).并且两组TG、FPG、γ-GGT、UA的平均浓度,脂肪肝组明显高于非脂肪肝组,两者差异具有统计学意义(P<0.01).结论 高血脂、高血糖是诱发脂肪肝的重要因素,脂肪肝患者是发生肝病、痛风和心脑血管病的高发人群,领导干部健康问题不容忽视,应加强锻炼,合理膳食,积极治疗,提高身体健康水平. 相似文献
55.
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57.
XU Tian WANG Wei ZHAI Lin ZHANG Yun Feng ZHOU Hong Zhi WU Xin Min LI Ai Hong XIE Li Li NING Xiao Jin JI Yu Teng WANG Hong Mei KE Kai Fu 《Biomedical and environmental sciences : BES》2017,30(3)
Objective We aim to explore the potential association between serum gamma-glutamyl transferase levels and functional outcome after aneurysmal subarachnoid hemorrhage in a Chinese population. Methods A total of 386 aneurysmal subarachnoid hemorrhage patients were included in the study from September 2007 to February 2015. Baseline serum gamma-glutamyl transferase levels and 6-month follow-up functional outcomes were determined. A poor outcome was defined as a modified ranking scale score of ≥ 3. The multivariable logistic model was used to analyze the relationship between serum gamma-glutamyl transferase and clinical outcomes after aneurysmal subarachnoid hemorrhage. Results The adjusted poor outcome rates of patients with gamma-glutamyl transferase levels of 30 U/L, 30-50 U/L and ≥ 50 U/L were 16.7%, 19.6%, and 34.4%, respectively(P 0.01). The age-sex and multivariable adjusted odds ratios(95% confidence intervals) of poor prognosis comparing the top group(≥ 50 U/L) with the lowest group( 30 U/L) were 5.76(2.74-12.13), 6.64(2.05-21.52), and 6.36(1.92-21.02). A significant linear trend existed between gamma-glutamyl transferase level and aneurysmal subarachnoid hemorrhage prognosis. This association was also observed among nondrinkers. Conclusion Patients with higher gamma-glutamyl transferase levels were more likely to have a poor prognosis. Serum gamma-glutamyl transferase can be considered to be an independent predictor of functional outcomes after aneurysmal subarachnoid hemorrhage. 相似文献
58.
We summarized the findings of toxicity studies on graphene-based nanomaterials (GNMs) in laboratory mammals. The inhalation of graphene (GP) and graphene oxide (GO) induced only minimal pulmonary toxicity. Bolus airway exposure to GP and GO caused acute and subacute pulmonary inflammation. Large-sized GO (L-GO) was more toxic than small-sized GO (S-GO). Intratracheally administered GP passed through the air-blood barrier into the blood and intravenous GO distributed mainly in the lungs, liver, and spleen. S-GO and L-GO mainly accumulated in the liver and lungs, respectively. Limited information showed the potential behavioral, reproductive, and developmental toxicity and genotoxicity of GNMs. There are indications that oxidative stress and inflammation may be involved in the toxicity of GNMs. The surface reactivity, size, and dispersion status of GNMs play an important role in the induction of toxicity and biodistribution of GNMs. Although this review paper provides initial information on the potential toxicity of GNMs, data are still very limited, especially when taking into account the many different types of GNMs and their potential modifications. To fill the data gap, further studies should be performed using laboratory mammals exposed using the route and dose anticipated for human exposure scenarios. 相似文献
59.
Songming Ding Shanjie Dong Hengkai Zhu Weilin Wu Yiting Hu Qiyong Li Shusen Zheng 《The Journal of international medical research》2021,49(11)
ObjectiveCommon bile duct (CBD) stones can spontaneously pass through the papilla. This study explored factors associated with stone passage by comparing differences in the clinical features of stones retained in the CBD and excreted stones.MethodsData were retrospectively collected for all patients who were hospitalized in our center between March 2016 and May 2021 with clinical, laboratory, or imaging evidence of CBD stones. All patients underwent endoscopic retrograde cholangiopancreatography (ERCP) and were classified into two groups: group A (stones extracted by ERCP, n = 86) and group B (stones discharged before ERCP, n = 15). Demographic data, biochemical and radiological findings were compared between the groups.ResultsStone size (0.82 vs. 0.33 cm), and levels of total bilirubin (58.2 vs. 28.8 μmol/L), gamma-glutamyl transpeptidase (416.7 vs. 193.9 U/L), alkaline phosphatase (191.9 vs. 123.1 U/L), carbohydrate antigen 19-9 (603.7 vs. 37.2 U/mL), and α-L-fucosidase (37.4 vs. 22.6 U/L) were significantly higher in group A than in group B. Logistic regression analyses showed that stone size was the only factor significantly associated with spontaneous passage of CBD stones.ConclusionsCBD stones less than 0.33 cm in size may be self-expelled through the papilla. 相似文献
60.
Many carcinomas in humans are rich in γ-glutamyl transpeptidase (GGT), a plasma membrane enzyme that reacts with extracellular substrates. Thus, biochemical targeting of chemotherapeutic agents may be achieved by converting anticancer drugs into their γ-glutamyl derivatives. Chemical conversion of phenylhydrazine (PH) and biochemical modification of daunomycin (DM) into their γ-glutamyl derivatives γ-glutamyl phenylhydrazine (GGPH) and γ-glutamyl DM (GGDM) resulted in the abolishment of their mutagenicity and cytotoxicity, as judged by decreased viability and increased mutant yields in cultures of several Salmonella Ames strains. Commercial γ-glutamyl-p-nitroanilide (GGPNA) was not toxic or mutagenic. Mutagenicity and/or cytotoxicity of these γ-glutamyl derivatives were restored upon reaction with GGT, with concomitant release of PH, and p-nitroaniline (PNA). The GGT-dependent release of DM from GGDM was demonstrated by thin layer chromatography (TLC), spectral analysis, and specific mutagenicity. Mutagenicity and/or cytotoxicity of γ-glutamyl derivatives increased in the presence of glycylglycine, a GGT activator, and decreased in the presence of serine-borate, a GGT inhibitor. GGDM retained considerable DNA binding capacity. Its inability to kill and mutagenize was due to altered transport properties. The results are compatible with the notion that γ-glutamylation is a feasible method for biochemical targeting of drugs containing a primary amino group to GGT-rich tumors. Environ. Mol. Mutagen. 32:377–386, 1998 © 1998 Wiley-Liss, Inc. 相似文献